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// ============================================================================
// Copyright (c) 2017-2019 Nawapunth Manusitthipol (NawaMan - http://nawaman.net).
// ----------------------------------------------------------------------------
// MIT License
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
// ============================================================================
package functionalj.stream;

import static functionalj.function.Func.f;

import java.util.function.Function;

import lombok.val;


class StreamPlusMapAddOnHelper {
    
    @SafeVarargs
    static final  StreamPlus mapFirst(
            StreamPlusWithMapFirst  stream,
            Function ... mappers) {
        return stream
                .map(f(d -> {
                    Exception exception = null;
                    boolean hasNull = false;
                    for(val mapper : mappers) {
                        try {
                            val res = mapper.apply(d);
                            if (res == null)
                                 hasNull = true;
                            else return (T)res;
                        } catch (Exception e) {
                            if (exception == null)
                                exception = e;
                        }
                    }
                    if (hasNull)
                        return (T)null;
                    
                    throw exception;
                }));
    }
    
}

public interface StreamPlusWithMapFirst {
    
    public  StreamPlus map(
            Function mapper);
    
    //== mapFirst ==
    
    public default  StreamPlus mapFirst(
            Function mapper1,
            Function mapper2) {
        return StreamPlusMapAddOnHelper
                .mapFirst(this, mapper1, mapper2);
    }
    
    public default  StreamPlus mapFirst(
            Function mapper1,
            Function mapper2,
            Function mapper3) {
        return StreamPlusMapAddOnHelper
                .mapFirst(this, mapper1, mapper2, mapper3);
    }
    
    public default  StreamPlus mapFirst(
            Function mapper1,
            Function mapper2,
            Function mapper3,
            Function mapper4) {
        return StreamPlusMapAddOnHelper
                .mapFirst(this, mapper1, mapper2, mapper3, mapper4);
    }
    
    public default  StreamPlus mapFirst(
            Function mapper1,
            Function mapper2,
            Function mapper3,
            Function mapper4,
            Function mapper5) {
        return StreamPlusMapAddOnHelper
                .mapFirst(this, mapper1, mapper2, mapper3, mapper4, mapper5);
    }
    
    public default  StreamPlus mapFirst(
            Function mapper1,
            Function mapper2,
            Function mapper3,
            Function mapper4,
            Function mapper5,
            Function mapper6) {
        return StreamPlusMapAddOnHelper
                .mapFirst(this, mapper1, mapper2, mapper3, mapper4, mapper5, mapper6);
    }
}